JPS6278051A - End section of can made of metal with cover made of plastic - Google Patents

Abstract

A metal can end with a tear-open plastics closure in which the closure has a plug part (14) fitting into an aperture (11) in the can end, a rim (17) surrounding the plug part, an d a pull tab (15), wherein a groove (22) extends across the plug part (14) and aligned grooves (24,25) or interruptions extend across the rim (17) to provide a hinge line allowing the tab (15) and the adjacent portion (23) of the plug part to pivot upwardly to provide venting of the can in a first stage of opening before full opening of the closure in a second stage. The closure (12) is of the kind which is moulded on to the can end (10) so as to totally enclose a downturned flange (16) around the periphery of the aperture (11), and to be capable of being sheared against the flange on opening, and the residual thickness of the plastics material below the flange (16) is greater in the main portion than in the vent portion (23) of the closure to provide a temporary arrest after venting. The plug part (14) is stiffer than the metal of the can end so that doming of the can end under internal pressure is concentrated in the metal and the pull tab (15) extends at an angle to the can end surface, rendering it easier to grasp for opening the aperture. A second hinge line may be provided at the far end of the closure, with a further increase in residual thickness, so that the closure can be retained on the can end while being hinged out of the way for pouring.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application] The present invention relates to the end of a metal can of the type that closes the opening with a pull-open plastic lid having a laterally extending pull tab for opening the opening; In particular, it relates to the end of a metal can for containing a liquid that generates internal pressure, such as a carbonated beverage.

[Prior Art and Problems to be Solved by the Invention] In the conventionally known structure in which only one large opening is made at the end of a metal can and this is closed with a lid having a uniform cross-sectional shape,
As soon as the lid is lifted from one end of the opening, it will peel off immediately, and it is impossible to do anything in the meantime.
This creates an unpleasant noise and even risks spilling the contents of the can. It is also known to provide two openings. In other words, the vent hole and spout are opened in sequence to reduce noise and reduce the risk of spillage. But for this structure.

Another drawback is that the manufacturing of the can ends is complicated.

[Means, operations and effects for solving the problems] Thus, an object of the present invention is to provide an end portion of a single-opening metal can whose lid can be opened with care so as to reduce noise and reduce the risk of spillage. The goal is to provide the following.

According to the present invention, the end of the metal can is closed with a pull-open plastic lid having an opening surrounded by a downwardly formed flange made of metal material at the end of the can, and the lid is fitted into the opening. a plug portion, a rim surrounding the plug portion and overlying the can end metal material around the opening, and nine laterally extending tabs molded as an integral part of the lid;
The lid is molded onto the end of the can so as to surround the entire flange, but when the tab is pulled up, it is sheared at the flange and the lid opens. a groove extending across the plug portion, the groove forming a hinge line for bending the tab and an adjacent portion of the plug portion upwardly relative to the remainder of the plug portion; The rim, however, was reduced in thickness or provided with notches so that it did not substantially resist the hinge action, thus allowing ventilation of the can before the lid was fully opened. At the end of a metal can with a plastic lid, the remaining plastic material below the flange is thicker on the side of the lid opposite the tab across the pin line than on the side adjacent to the tab. In this way, an end of the metal can is provided which temporarily retains the shearing action and allows time for venting before the lid is fully opened. The effect of this configuration is that the process of opening the lid is two-fold.
Divided into stages. First, as a first step, the aperture comparison /I
The can is vented through the X-shaped section, and then tempered by temporary restraint before entering the second stage and opening the opening completely. As a result, the noise generated during the process of opening the lid and the risk of spilling the contents are greatly reduced. By increasing the thickness of the plastic material remaining under the flange in the area remote from the tub, it is possible to increase the safety against leakage due to creep phenomena of the plastic material during storage of the can under internal pressure.

Preferably, the plug portion of the lid has a higher resistance to bending than the metal material of the can end, at least in a portion remote from the laterally extending pull tab, so that the can end is subjected to internal pressure within the can. When curving into a dome shape, said portion of the lid strengthens the portion of the can end around it, so that the curvature primarily occurs in the remaining portion of the can end. As a result, an angle is formed between the laterally extending tab and the adjacent surface of the can end. In this way, the end of the tab is separated from the can end, making it very easy to pinch when lifting the tab to open the opening. Although the plug portion bends at the hinge, the portion of the plug portion adjacent to the pull tab remains largely unbent, so that only the pull tab separates from the dome-shaped curved surface of the can end.

By making the plug part with an appropriate thickness, it is possible to impart a desired bending resistance to the plug part. If the lid is made of a relatively stiff plastic material and the rim thickness is uniform, the stiffness of the plastic material will prevent the area adjacent to the tab from breaking at the hinge line when the tab is lifted. Rather than bending, the entire lid bends in a large circular arc shape, resulting in the unexpected result that the lid opens completely in the first step. Reduce the thickness of the rim co-linear with the groove so that there is no substantial resistance to hinging action, or
Alternatively, the rim may be cut out in line with the groove so that there is no resistance to the hinge action, for the reasons mentioned above. The use of a plug part that exhibits relatively high resistance to bending also helps to avoid the unintended consequence of the entire lid bending and opening fully in the first step.

If the opening and the plug portion of the lid have parallel extending side edges and a semicircular end, a tab extends from one semicircular end of the plug portion, and the semicircular end from which the tab extends; Preferably, a groove is provided across the plug part where the plug part meets the parallel side edges of the plug part. Preferably, the groove has a V-shaped cross-sectional shape and the depth of the groove is approximately equal to half the thickness of the plug portion of the lid.

In an embodiment, a second groove extends across the plug portion abutting the parallel side edges and the semi-circular end remote from the connection to the tab, and the rim of the lid is flush with the second groove. It is thinned or notched at the line to form the second hinge line, and the thickness of the plastic material remaining under the flange at the semicircular end far from the tab is less than that at the parallel side edges. It can also be thickened to provide sufficient strength to resist shearing, so that the lid remains attached to the end of the can when bent at the second hinge line.

The invention also extends to metal cans having ends as described above.

Hereinafter, the present invention will be explained in more detail by way of examples with reference to the accompanying drawings.

〔Example〕

As shown in Figures 1-4, an opening 1 is provided at the end 10 of the metal can.
1 (Fig. 4), and close this opening with the plastic lid 1.
Close at 2. The lid 12 includes a plug portion 14 that fits into the opening 11, and a ring-shaped pull tab 15 that is integrally molded with the lid body and extends laterally. The area around the opening 11 is
The metal material of the can end 10 is surrounded by a downwardly bent flange 16. To fit the lid onto the can end, the flange 16 is molded to surround the entire flange 16, and the inner rim is brought into close contact with the underside of the can end 10. Pulling up on the tab 15 tears the plastic at the flat end 161 of the flange 16 so that the lid can be opened.

The lid 10 is provided with an upper side rim 17 on the front side.

This rim surrounds the plug portion 14 and fits tightly against the surface of the can end 10. As shown in Figure 1, the plug part 1 of the lid
4 (and thus also the aperture 11 in which it fits) is oblong with parallel sides 18, 19 and semicircular ends 20, 21.

The surface 141 of the plug portion 14 is connected to the center panel 101 of the can end.
It is recessed lower than the surrounding rim 17 so that it is almost flush with the rim. A groove 22 is provided across the longitudinal direction of the lid and across the surface of the plug portion 14. The groove 22 traverses the plug part 14 where the semi-circular end 20 near the tab 15 meets the parallel side of the plug part, and connects the tab 15 and the adjacent part 23 of the plug part to the rest of the plug part. form a hinge line that makes it easier to bend upward.

Thus, as shown in Figure 4, the can can be vented as a first step before the lid is fully opened.

As clearly shown in FIGS. 2 and 3, the groove 22 has a figure-7 cross-sectional shape, and the depth of the groove is equal to that of the plug portion 14.
Reduce the thickness to approximately half that of the previous one.

In order to ensure that the rim 17 does not offer any substantial resistance when folding the portion 23 of the plug part 14 relative to the rest of the lid, the rim 17 is designed to provide substantial resistance, especially when a rigid plastic material such as nylon is used. In order to prevent the rim from becoming difficult to bend, the rim 17 is also provided with grooves 24 and 25 on the same straight line as the groove 22, and the depth of the groove is at least half the thickness of the rim 17. The thickness should be such that when the portion 23 is bent, the remaining material at the bottom of the grooves 24, 25 is torn off.

Further, as shown in FIGS. 2 to 4, the thickness of the plug portion 14 of the lid is made thinner at a portion 23 adjacent to the tab 15. As a result, the thickness of the remaining plastic material below the end 161 of the flange 16 is reduced by the groove 2 relative to the pull tab 15.
The portion 29 opposite the tab 2 is thicker than the portion 23 adjacent to the tab. The reason why the remaining portion is thickened in this manner is to temporarily retain the shearing action after the lid portion 23 is lifted to open the vent hole as shown in FIG. Next, to open the main part of the lid, press the plug part 14.
so that the parallel sides 18, 19 of the This leaves some thickness below flange 16, but only a small amount of additional force is required. However, the fact that the degree of force application is discontinuous and there is a joint in the middle means that the internal pressure of the can causes the shearing action of the sides 18 and 19 to continue, and as a result, the lid is blown off from the end of the can. Effective in reducing risks.

Due to the internal pressure of the filled can, the end of the can is curved into a dome shape, as shown in FIG.

If the plug part 14 is made of a relatively thin material that has less resistance to bending than the metal material of the can end, the bending of the can end due to internal pressure will occur preferentially around the opening 11, and The plug portion 14 will bear the substantial bending, and the metal portion 28 below the pull tab 15 will undergo less bending. As a result, the pull tab 15 comes into close contact with the end surface of the metal can, making it difficult to pinch. In particular, as a result of the molding process, the sides of the pull tab 15 are inclined to conform to the surface of the end of the can, making it twice as difficult to grasp. In the case of the can end shown in Figs. 1 to 4, the plug part 1
4 is of sufficient thickness to provide greater resistance to bending than the metal of the can end 10. Even if the end of the can bends as shown in FIG. 3 due to internal pressure, the plug portion 14 hardly bends except for the hinge portion formed by the groove 22. In particular, the portion 29 far from the pull tab 15 does not bend, and the can end portion around this portion 29 becomes strong. on the other hand,
The metal portion 28 of the can end below the pull tab 15 is highly curved. This is due to the thick plug portion 14
This is because the curvature is concentrated at the center and hinge portions of the can end due to the additional bending resistance applied to the metal material adjacent to the can end. As a result, as shown in FIG.
An angle is formed between the lid and the adjacent surface of the can end, making it very easy to pinch when opening the lid.

The fact that the portion 29 of the plug portion 14 exhibits strong bending resistance means that
This is particularly important. That is, it is doubly advantageous that this section 29 is thicker than the rest of the plug part. Since this section 29 is thicker, and therefore the plastic material remaining below the flange 16 at the end of the lid far from the tab 15 is also thicker, the creep phenomenon of the plastic material that occurs when cans under internal pressure are stored for long periods of time is reduced. This provides additional safety against possible leaks as a result.

When the can end is not subjected to internal pressure, its central portion is not curved but flat, and the pull tab 15 is in close contact with the can end portion 28 as shown in FIG. This condition is advantageous in that it saves storage space in stacking can ends before use.

In an alternative embodiment shown in FIGS. 5 and 6, the rim 17 is not only provided with grooves 24, 25, but also has cutouts 26, 27 co-linear with the groove 22 to provide a hinge action as shown in FIG. so that there is no resistance to it. In other respects, this embodiment is completely similar to the embodiments shown in FIGS. 1-4.

Also in the case of the third embodiment shown in FIGS. 7 to 11, the can end 10
, the opening 11 and the flange 16 are the same as shown in the previous drawings.

The lid 30, as before, has a plug portion 31 that includes a side rim 22 integrally molded with the can end 10 so as to surround the flange 16, but the pull tab 33 is attached to the rim 32 as shown. It is formed into a loop having a side member or arm 34 surrounding the lid and joining the rim at the left end of the lid.

A finger knob 35 is provided at the right end of the pull tab 33.

A groove 36, corresponding to the groove 22 of FIGS. 1-6, extends across the plug portion 31 of the lid where the semicircular left end portion 37 and the rectangular main portion 39 meet, forming a vent.

A groove 38 is also provided in the rim 32, colinear with the groove 36.

The rectangular main part 39 of the plug part is then made thicker than the vent part 37 so that the remaining plastic material below the flat end 161 of the flange 16 is thicker at the main part 39, as in the previous embodiment. , after opening the vent, the shearing action is retained, albeit temporarily.

In this embodiment, a second groove 40 is provided across the semicircular end 41 far from the coupling part with the tab 33 and the plug part 31 that contacts the rectangular part, and a second groove 40 is provided on the rim on the same straight line as this groove 40. A groove 42° 43 is made across 32 to serve as a second hinge line. The thickness of the plastic material remaining under the flange 16 is sufficiently thicker at the semi-circular end 41 than at the rectangular section so that it is less likely to shear.
As a result, in order to open the lid 30, the main part 30 starts with the first step of venting as shown in FIG.
is opened, but the lid remains attached to the can by the end 41. The main portion 39 then bends at the second hinge line so that the contents of the can can be poured out.

[Brief explanation of drawings]

FIG. 1 is a plan view of the end of a metal can with a plastic lid according to the present invention attached; FIG. 2 is an enlarged sectional view of the end of the can shown in FIG. 1; FIG. FIG. 4 is a view similar to FIG. 2 showing the can end inflated by internal pressure; FIG. 4 is a view similar to FIG. 2 showing the opening of the lid in the first step of the process; FIG. FIG. 6 is a sectional view similar to FIG. 4 for explaining the first step of opening the lid shown in FIG. 5; FIG. 7 is a plan view similar to FIG. FIG. 8 is a sectional view similar to FIG. 2 of the third embodiment; FIG. 9 is a partially enlarged sectional view; FIG. 10 is a drawing similar to FIG. 8, showing the first step of opening the lid; FIG. 11 is a drawing similar to FIG. 8, further showing the second step. [Explanation of main symbols] 10... End of can, 11... Opening, 12...
Lid, 14... Plug part, 15... Pull tab, 16... Flange, 17... Rim,
22...Groove, 23...Tab adjacent portion, 24
．． 25... Groove.

Claims (7)

[Claims] (1) The end of a metal can is such that an opening surrounded by a downwardly formed flange made of metal material at the end of the can is closed with a pull-open plastic lid, and the lid has a plug part that fits into the opening. , a rim surrounding the plug portion and overlapping the can end metal material around the opening, and a laterally extending tab molded as an integral part of the lid, the lid being attached to the can end so as to surround the entire flange. The lid is molded but is sheared at the flange when the tab is pulled up to open the lid, and the lid is provided with a groove extending transversely to the longitudinal direction of the tab and across the plug portion of the lid. This groove forms a hinge line for bending the tab and adjacent portion of the plug portion upwardly relative to the rest of the plug portion, and in line with the groove the rim is reduced in thickness or notched. at the end of a metal can with a plastic lid, below the flange, so as to provide substantially no resistance to the hinge action, thus allowing ventilation of the can before the lid is fully opened. The remaining plastic material should be thicker on the side of the lid opposite the tab across the hinge line than on the side adjacent to the tab to temporarily retain the shearing action and completely remove the lid. end of a metal can with a plastic lid, adapted to allow time for ventilation before opening. (2) The plug portion of the lid, at least in the portion remote from the laterally extending pull tab, should have a higher resistance to bending than the metal material at the end of the can, so that the end of the lid can form a dome under the internal pressure of the can. When curving into shape, said portion of the lid stiffens the portion of the can end around it, so that the curvature primarily occurs in the remaining portion of the can end, so that the sideways extending tab and the adjacent surface of the can end The end of a metal can according to claim 1, characterized in that an angle is formed between the ends. (3) the opening and the plug portion of the lid have parallel extending side edges and a semicircular end, a tab extends from one semicircular end of the plug portion, and a semicircular shape from which the tab extends; Claim (1), characterized in that a groove is provided across the plug part where the end part and the parallel side edge of the plug part are in contact with each other.
Or the end of the metal can described in (2). (4) The groove has a V-shaped cross-sectional shape, and the depth of the groove is approximately equal to half the thickness of the plug portion of the lid. end of metal can. (5) The tab is shaped like a pull ring, and the tab is provided with thin fins made of plastic material along the inside of the ring to serve as a cushion when the operator pinches the tab with his/her fingers. An end portion of a metal can according to any of the preceding claims. (6) a second groove extends across the plug portion abutting the parallel side edges and the semicircular end remote from the connection to the tab, and the rim of the lid is colinear with the second groove; the thickness of the plastic material remaining under the flange at the semicircular end remote from the tab is greater than at the parallel side edges; Claim (3) characterized in that the lid has sufficient strength to resist shearing when folded at the second hinge line, so that the lid remains attached to the end of the can when folded at the second hinge line. The end of the metal can according to either (4) or (5). (7) A metal can having an end portion of the metal can according to any of the above-mentioned claims.